BY MIKE WALSH In 1951, at age 25, a young woman named Vivian Maier moved from France to New York City, where she worked for some time in a sweat shop. Maier also had a camera, and she spent much of her free time walking around NYC working class neighborhoods taking photos of people, places, and buildings. She used a Rolleiflex camera, the type you look down into a two-inch lens to aim and focus. It used 120 mm film, a large format that, in the hands of someone like Maier, can capture incredible richness, detail, and depth of field. […]